============================= WARNING: suspicious RCU usage 5.12.0-rc5-syzkaller #0 Not tainted ----------------------------- kernel/sched/core.c:8294 Illegal context switch in RCU-bh read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 1 lock held by syz-executor.1/20199: #0: ffff888013a14058 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff888013a14058 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x2d8/0x1120 arch/x86/mm/fault.c:1331 stack backtrace: CPU: 1 PID: 20199 Comm: syz-executor.1 Not tainted 5.12.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x176/0x24e lib/dump_stack.c:120 ___might_sleep+0x6e/0x530 kernel/sched/core.c:8294 process_huge_page mm/memory.c:5051 [inline] clear_huge_page+0x208/0x8a0 mm/memory.c:5112 __do_huge_pmd_anonymous_page+0x286/0xde0 mm/huge_memory.c:607 do_huge_pmd_anonymous_page+0x552/0xac0 mm/huge_memory.c:772 create_huge_pmd mm/memory.c:4189 [inline] __handle_mm_fault mm/memory.c:4424 [inline] handle_mm_fault+0x1fe4/0x2570 mm/memory.c:4551 do_user_addr_fault+0x8ce/0x1120 arch/x86/mm/fault.c:1390 handle_page_fault arch/x86/mm/fault.c:1475 [inline] exc_page_fault+0xa1/0x1e0 arch/x86/mm/fault.c:1531 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:577 RIP: 0033:0x461bdb Code: 80 fa 01 77 3b 72 05 0f b6 0e 88 0f c3 c5 fa 6f 06 c5 fa 6f 4c 16 f0 c5 fa 7f 07 c5 fa 7f 4c 17 f0 c3 48 8b 4c 16 f8 48 8b 36 <48> 89 4c 17 f8 48 89 37 c3 8b 4c 16 fc 8b 36 89 4c 17 fc 89 37 c3 RSP: 002b:00007ffc2e06e7e8 EFLAGS: 00010206 RAX: 0000000020000000 RBX: 0000000000000003 RCX: 0023617363762f76 RDX: 000000000000000b RSI: 7363762f7665642f RDI: 0000000020000000 RBP: 00007ffc2e06e8a8 R08: 0000000000970000 R09: 0000000000000010 R10: 00007ffc2e1030b8 R11: 000000000001270a R12: 0000000000000001 R13: 0000000000000000 R14: 000000000056bf60 R15: 000000000005fbb2